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Technology and Health News

All kinds of interesting tech and health news from around the World!

Technology and Health News > Wednesday, February-25-2009

Magnetic semiconductors at room temperature


The new devices can operate at 30 degrees above zero, rather than less than 70. This is the characteristic of the new generation of semiconductors, researched at the Italian Institute for the Physics of Matter (INFM-CNR), and in the Ludwig Maximilian University in Monaco of Bavaria and the ETH Zurich (the study).

Today there are two ways to record information on a medium: the electronic format, in which the binary language is the passage of electrons (the transistors) and magnetic (MRAM memory), more recently, in which the binary language is given by state of magnetization. To communicate these two systems could boost significantly the computational schemes, pending the distant quantum computer. Doubling the processing power and memory of a chip while maintaining the size, without the need to go in nano-scale (a scale, that is, a billionth of a meter) are just two of the technology that promises magnetic semiconductors suggest a near future.

These devices were made over ten years ago, but so far required temperatures far below zero to work. The problem now seems outdated as the known semiconductors gallium arsenide containing traces of manganese, a metal which has ferromagnetic properties at around 200 degrees below zero. To increase the temperature threshold, above which the ferromagnetic behavior disappears, the researchers deposited on a semiconductor film of iron - metal known for its magnetic properties - the thickness of a few nanometers.

Iron and manganese interacted so effectively that the new material, has a ferromagnetic behavior up to 30 degrees above zero, a jump of over a hundred degrees above the starting temperature.

This result is a technological response parallel to that of the race to miniaturization and the research was selected the American Physical Society as one of the most important published in Physical Review Letters
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Technology and Health News > Tuesday, February-10-2009

Two shots for the nano-magnets


A new instrument to simultaneously measure the magnetic field and the atomic structure of matter at the nanoscale has been developed. The applications of this are future generations of high-density memories

Snapshots of the weakest and microscopic magnetic fields generated by just a few molecules of a nanometer (billionth of a meter). The researchers have obtained the S3 Center of the National Institute for the Physics of Matter (INFM-CNR) of Modena and the University of Modena .

This is a scanning microscope combined with a new highly sensitive magnetic sensor. The microscope scans close with his point - made up of a few atoms - the area of the test and how it relates to the roughness with a resolution of several nanometers. Beside the point, the sensor records the magnetic field intensity, but with high detail ( millionth of a meter).

In this way the researchers were able to get together for the first time, images of atomic structure and magnetic properties of a thin layer of nano-magnet on a support of silicon.

"The microscope allows us to measure directly the properties of nano-molecular magnets on the surface, even at temperatures close to absolute zero, to minus 270 degrees," says Marco. "Above all," says the researcher, "it helps us to understand the magnetism on the molecular scale."

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Technology and Health News > Thursday, January-29-2009

A switch for neuronal regeneration


For the first time a gene was identified that allows the repair of damaged nerves in nematodes. The study is from Science Express.

A gene that can stimulate the growth of nerve cells was first identified by researchers at the University of Utah (USA), thanks to cutting-edge experimental techniques and a huge genetic screening on a nematode (cylindrical or worm).

The neurons, which in the embrio are able to regenerate, in adults have their capacity to "repair" reduced or absent. In other words, damage to the central nervous system (brain or spinal cord) and its consequences - paralysis, loss or reduction of cognitive faculties - are permanent.

"In the past molecules have been identified that can inhibit the growth of neurons in different organisms," says the coordinator of research Michael Bastiani, "but their removal in the laboratory had no effect. That is why we went to look for those genes that can stimulate rather than inhibit, the regeneration of nerve. "

Taking as a experimental model flat worms (Caenorhabditis elegans), biologists have searched for the genes that trigger the regrowth of motor (neurons that "command" voluntary muscles): in practice, with an experimental technique called RNA interference to "shut down ", one by one, 5000 on 20,000 genes in the DNA of worms (genes similar are also present in humans).

The analysis led to the identification of dlk-1, which appears to play a key role in the regeneration of nerve tissue, and three other genes responsible for the formation of axons (parts of the neuron that conduct electrical signal).

The researchers found that in nematodes, the gene dlk-1 not only triggers a chain of events known as "Map kinase" behind the growth of neurons, but also that their regeneration can be increased or decreased by stimulating the gene to produce amounts more or less high of the protein dlk-1.

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Technology and Health News > Friday, January-09-2009

P21, the protein of immortality for cancer cells

The molecule slows the proliferation of tumor cells while giving the time needed to repair the damage to their DNA. The discovery, made by Italian researchers IEA, is published in Nature.

The secret of immortality of cancer stem cells - those that feed it and cause relapses because they're immune to chemotherapy - was unveiled. Their strength is the p21 protein that slows the proliferation, giving them the time needed to repair damage to DNA. In practice, it is as if these cells were able to rejuvenate indefinitely: no age, and thus do not die. By blocking the production of p21, however, you can make them vulnerable and hit the tumor at the root.

The research was conducted in the laboratories of the European Institute of Oncology (IFOM-IEO) in collaboration with the universities of Milan and Perugia, and was published this week in Nature.

The cells age and die because they accumulate damage and mistakes borne of DNA during cell divisions. To understand why this does not happen in a cancerous stem cell, the researchers observed what happens to a staminale "normal" when you alter one of the genes (oncogenes) that cause cancer (in this case, the acute myeloid leukemia).

The study revealed that oncogenes stimulate the activity of another gene, called p21, and thus the production of the corresponding protein, whose effect is to slow the proliferation. In essence, these cells have much more time to repair other damaged DNA, and remain young and active, immune to chemotherapy drugs because they recognize and affect only the cells in rapid proliferation.

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Technology and Health News > Monday, December-15-2008

A controlled Superconductor

The switch that turns off and on to command the superconducting property of the new device is a trivial electric field. In practice, what has been done by Andrea Ankle and colleagues at the University of Geneva in the first superconducting transistors. The operation, represents a milestone of applied physics and paves the way for the development of a new generation of microchips - and therefore computers - much faster than at present.

To understand how and why the device is considered so promising it must be from another discovery, made last year by the same group of university research in Switzerland and published in Science. In one study, physicists have created a single crystal in which two metal oxides (strontium titanate and lanthanum aluminate) are separated. Between these two materials, researchers have found a layer of free electrons (electronic cloud) and 0.3 Kelvin - that is just above absolute zero - traveling without any resistance. At that temperature, the crystal becomes a superconductor.

Scientists have now discovered how to turn off and turn on the superconductivity of this crystal at will, or modules, simply by applying an electric field to the point of contact between the two oxides. The result is a version of superconductive field effect transistors (FET) devices known in applied physics, able to switch from one state to a semiconductor insulator, and basic digital information in electronics (the fact that the current can pass or not is used as a binary 1-0 to store information).

As the field effect transistors is a semiconductor, however, it always has resistance to the passage of current. This means that the speed at which you can get the electrons when the device is "on" is limited which means heat develops beyond a certain limit. This side effect is damaging the transistor.

A superconducting transistor, however, can pass electrons (and record information) much more quickly, as it does not oppose any resistance to the passage of current and, therefore, not heat. There remains the problem of extremely low temperatures required for superconductivity. A limit that research is a long time trying to overcome.

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Technology and Health News > Thursday, December-04-2008

The friction slips away

A highly resistant and self lubricating material has been discovered, thanks to the formation of an oxide surface that captures the water vapor

Hard as diamond and slippery as a sheet of ice. The secret of the extraordinary characteristics of Bam, a special alloy-ceramics produced by blending a mix of boron, aluminum and magnesium (AlMgB14) with titanium boride (TiB2), was unveiled by researchers of Ames Laboratory, in Iowa (Usa ), who had accidentally discovered it a decade ago.

In 1999, researchers tried to obtain a substance capable of generating electricity if overheated, when, unexpectedly, found in the hands a league owned by the exceptional and seemingly inexplicable. The Bam is tough, despite possessing a complex structure, asymmetrical and not compact. Moreover, says Alan Russel of Iowa University, it is inherently slippery. One characteristic that, according to researchers, could be due to the formation on the surface of boron oxide, which can attract water molecules present in the air.

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Technology and Health News > Tuesday, November-25-2008

Nanotechnology: Nano-Tex Resists Spills

Researchers have made a fabric, made from polyester fibres which is coated with millions of small silicone filaments. This the most water-resistant clothing which was ever created by man.

Because of the nanometre-scaled filaments, a coating which stops water particules from going through the coating to the polyester fibres which are underneath. This mixture between a hydrophobic surface and a nanostructure coating leads to a super-hydrophobic effect.

This is similar to the surface of Lotus leaves. There are many applications for this: from stain resistant clothing (see video) to reducing water drag in submarines or swimmers. This could lead in a drag decrease of up to 20%.
Here's a little video from the Today Show with a stain resistant shirt which usese nano-technology (Nano-Tex material).


Technology and Health News > Thursday, November-20-2008

Carbon nanotube speakers

An amazing material was developed by Chinese scientists which is composed of carbon nanotube films and has a possible application (among otther) to produce the world's thinnest speakers.

Nanotubes, are a new carbon breed of material, which is 1000 times smaller than the width of a hair and can give sound with the "same quality of conventional speakers". This, however, does not require magnets of any sort or moving parts for that matter at all. You can easilly imagine speakers everywhere: on walls, helmets, thinner ear plugs or even on your shirt.

This is possible because very thin carbon nanotube films, with the right frequency of electric currents, can emit sound. It also has a wide frequency response range and high sound pressure.

It also turns out that they are practical to build, and are even stretchable. Here is a video with the actual speackers embedded in a flag!



Technology and Health News > Wednesday, November-12-2008

Leukemia has been sequenced

By comparing DNA of healthy and cancerous tissue of a single person, there were discovered eight new mutations linked to the disease. The study in Nature

The complete genome of a person suffering from cancer was decoded for the first time. The comparison between the DNA of normal and cancerous tissue of a woman suffering from acute myeloid leukemia (AML) has identified ten mutations in the genome of cancer cells, including eight so far unknown, which would be linked to the disease. Researchers of the Washington University School of Medicine (USA), coordinated by Richard K. Wilson, presented their findings in Nature.

Scientists have taken a sample of tissue from normal skin and a tumor tissue from bone marrow to a patient suffering from AML - cancer that affects the bone marrow cells that produce red blood cells. Subsequently they have decoded the DNA of the two tissues, comparing all three billion bases of which the genomes were composed, to go back to differences in disease characteristics of the individual.

There were ten mutations identified, two already known, eight first ever linked to the disease. Of those, three were found in genes that normally can block the growth of tumors (for example in Ptprt, the tyrosine phosphatase gene, often altered in colon cancer). Four changes instead involved genes regulate the molecular pathways that promote tumor development - particularly in a family of genes, usually expressed in embryonic stem cells, which could stimulate cell renewal. A final disturbing deterioration instead of transporting drugs into the cell. According to scientists, these mutations have occurred one after another, each adding something new to the tumor.

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Technology and Health News > Monday, November-03-2008

Fatal rewind

An enzyme that can rewind the DNA at points where the two propellers should remain separate, even fatal, causing disturbances.

The cause of some serious diseases, such as the rare immune-dysplasia of bone Schimke is a protein able to settle the two propellers of DNA at points in which they should remain separate and thus induce the expression of genes that would otherwise be idle.

Under normal circumstances the DNA presents a series of "bubbles", namely the segments in which there is space between them and raggomitolate. The unusual alignment of the two parallel strips, led by newly discovered protein, called Harp (HEPA-related protein), reactivates the expression of genes in these traits, which may in this way to start even occurrence of very serious diseases.

The enzyme is and was discovered by James Kadonaga and Timur Yusufzai, two biologists at the University of San Diego (California) authors whose research results were published in Science. Just as a zip, the enzyme flows on the tape of DNA tangles the lines and welding to the two separate entities, thereby according the traits of nucleic acid that ordinarily are designed to remain inactive. Exactly the opposite of what another enzyme, the "elicasi", which has the role to unwind the DNA during replication of the molecule, being essential for life.

The protein discovery is only the first of an entire class of enzymes candidates to be the basis of occurrence of disorders characterized by cardiac or kidney malfunction, with even fatal effects on children.

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